Diagnostic value of urinary microRNAs as non-invasive biomarkers for bladder cancer: a meta-analysis

Bladder cancer (BC) is the fifth most common malignancy worldwide. The expression levels of microRNAs (miRNAs) in urine samples of BC patients have been demonstrated to be different from healthy people. Several studies focusing on the diagnostic value of urinary miRNAs for BC detection have been reported. The aim of this meta-analysis was to access the overall diagnostic accuracy comprehensively and quantitatively.

PubMed, Embase, Web of Science, the Cochrane Library, and CNKI were searched without language restrictions for studies about the diagnostic value of miRNAs for BC. The pooled sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR, respectively), diagnostic odds ratio (DOR) were calculated using the random effects model. The summary receiver operating characteristic (SROC) curve was also generated and the area under the curve (AUC) was also reckoned to assess the diagnosis accuracy. Besides, Chi-square test and I(2) test were used to assess the heterogeneity between studies. Publication bias was evaluated by the Deeks' funnel plot asymmetry test.

Fourteen studies were included in this meta-analysis, with a total of 1,128 BC patients and 1,057 matched controls. The overall sensitivity, specificity, PLR, NLR and DOR of urinary miRNAs for the diagnosis of BC were 0.71 (95% CI: 0.67-0.75), 0.75 (95% CI: 0.70-0.79), 2.8 (95% CI: 2.3-3.4), 0.39 (95% CI: 0.33-0.46) and 7 (95% CI: 5-10), respectively. The area under the SROC curve was 0.79. Subgroup analyses suggested that the ethnicity and miRNA profiling had an obvious influence on the diagnostic accuracy.

The current analysis suggested that urinary miRNA panels may be a promising noninvasive biomarker in the diagnosis of BC.